The All Things D conference has been replaced by Re/code's Code Conference.
It won't have Tim Cook, but it will have both Eddy Cue and Craig Federighi. Jimmy Iovine is also speaking at the conference, and he might also be an Apple exec by then!
Aside from Apple execs, there are a lot of HUGE speakers at the conference, including the CEOs of Microsoft, Twitter, Netflix, General Motors, Nest, Qualcomm, Intel, Wal-mart, Comcast, Uber, Dropbox, Salesforce, Blackberry, and a few others. Also, Google's Sergey Brin will be speaking.
You can find out more
here.
The conference is in 2 weeks (May 27th-29th).